Recently, the development of multimedia applications boosts the need for image processing. The adjustment of the image dynamic range includes the brightness adjustment and the contrast adjustment. Conventionally, linear mapping models based on global or local features of an image is used to simply stretch or compress the image data. For example, conventional image processing technique may increase or decrease the global brightness of an image according a single adjusting function.
However, the abovementioned image processing method can not ensure that the color and details of the image is maintained in the effective dynamic range. Usually, stronger image adjustment causes the loss of color information and saturation.
Therefore, there is a need for an image processing method for dynamically adjusting luminance and contrast of image.